Composite materials prepared by coating metal reinforcing materials such as steel cords with rubber compositions for the purpose of reinforcing rubbers to enhance strength and durability thereof have so far been used for tires for cars, conveyor belts, hoses and the like, particularly rubber products to which strength is required.
The above rubber-metal composite materials require an adhesive property which is stable and less changed with the passage of time between rubber and a metal reinforcing material in order to exhibit a high reinforcing effect and obtain reliability.
Further, when rubber is adhered with metal, a method in which rubber and metal are bonded at the same time, that is, a direct vulcanization bonding method is known, and in this case, it is considered to be effective that a sulfeneamide base vulcanization accelerator which provides vulcanization reaction with a delayed action is used when vulcanization of rubber and bonding of rubber and metal are carried out at the same time.
At present, N,N-dicyclohexyl-2-benzothiazolylsulfeneamide (hereinafter abbreviated as “DCBS”) represented by the following formula is known as a vulcanization accelerator which provides vulcanization reaction with the largest delayed action among commercially available sulfeneamide base vulcanization accelerators:

Further, when a larger delayed action than that in vulcanization reaction by DCBS is required, a vulcanization retardant other than a sulfeneamide base vulcanization accelerator is used in combination. N-(cyclohxylthio)phthalimide (hereinafter abbreviated as “CTP”) is known as a representative vulcanization retardant which is commercially available, but it has already been known if this CTP is blended with rubber in a large amount, that it exerts an adverse effect on the physical properties of the vulcanized rubber and that it causes blooming which deteriorates the appearance of the vulcanized rubber and exerts an adverse effect on an adhesive property thereof.
Further, bissulfeneamide represented by a specific formula (refer to patent document 1) and benzothiazolylsulfeneamide base vulcanization accelerators (refer to patent document 2) obtained by using amine originating in natural fats and oils as a raw material are known as sulfeneamide base vulcanization accelerators other than DCBS described above.
However, with respect to the sulfeneamide base vulcanization accelerators described in patent documents 1 and 2, only rubber physical properties are disclosed, and the adhesion performances are neither described nor suggested therein. In addition thereto, it is neither described nor suggested at all that the sulfeneamide compound of the present invention can be used as a novel vulcanization accelerator for rubbers.
Further, several production processes for the sulfeneamide compounds used in the present invention are known, for example, in patent documents 3, 4 and 5, but it is neither described nor suggested at all that the above compounds can newly be used as a vulcanization accelerator for rubbers, and an adhesion performance with a steel cord which the above vulcanization accelerators provide is neither described nor suggested as well.    Patent document 1: Japanese Patent Application Laid-Open No. 2005-139082    Patent document 2: Japanese Patent Application Laid-Open No. 2005-139239    Patent document 3: EP0314663A1    Patent document 4: British Patent No. 1177790    Patent document 5: Japanese Patent Publication No. 1973-11214